Age-related hearing loss can be caused by physical changes in the ear, the auditory nerve or in the ability of the brain to process sound. Sometimes all three might be involved. Age-related hearing loss (presbycusis) is the loss of hearing that gradually occurs in older adults. Hearing loss is a partial or complete inability to hear; the onset occurs either suddenly or as a gradual decline in how well a person can hear. (1)
Vision loss is an inclusive term that covers all people who are blind or partially sighted, including people who have had no sight from birth, people who are legally blind as well as people with vision loss that impairs daily function. Vision loss can also be characterized by other forms of impairment
such as loss of depth perception or contrast sensitivity.
The sense of smell can be taken for granted until it deteriorates. The olfactory function declines with aging and causes a loss of the sense of smell and the ability to discriminate between smells.
The sense of touch includes perception of pressure, vibration, temperature, pain, position of the body in space and localization of a touch. Skin, muscles, tendons, joints and internal organs have nerve endings (receptors) that detect these sensations. Some receptors give the brain information about the position and condition of internal organs which helps to identify changes such as feeling pain from an internal organ. The sense of touch is the most intact of all senses in older adults and least impacted by advancing years.
Proprioception is the “sixth sense” that allows a person to determine where their body is moving in space. It is essential to normal execution of basic movements. One of the most common situations with postural imbalance is the occurrence of falls. Balancing is the process of controlling the body’s center of mass with respect to its base of support and depends on the integration of sensory systems (visual, vestibular and somatosensory) with the central nervous system (CNS).